(define (make-dictionary)
  (define (dictionary ls)
    (define (add_val ls key val found res)
      (cond
        ((not (eq? (is_contains ls key) #f))
        (define n (change_val ls key))
        (dictionary n)
        )
        (else (dictionary (append (cons key val) ls)))
        )

      (define (is_contains ls to_find)
        (cond
          ((null? ls) #f)
          ((equal? (caar ls) to_find) (car ls))
          (else (is_contains (cdr ls) to_find))
          )
        )

      (define (change_val ls old new_val)
        (cond
          ((null? ls) ls)
          ((equal? (car ls) old) (append (list new_val) (cdr ls)))
          (else (append (list (car ls)) (change_val (cdr ls) old new_val)))
          )
        )

        )

    (define (find_val lst key)

      (define (is_contains ls to_find)
        (cond
          ((null? ls) #f)
          ((equal? (caar ls) to_find) (car ls))
          (else (is_contains (cdr ls) to_find))
          )
        )

      (cond
        ((null? lst) #f)
        ((equal? (caar lst) key) (car lst))
        (else (is_contains (cdr lst) key))
        )

      )

  (define (choose_func param)
    (cond
      ((null? param) ls)
      ((pair? param) (dictionary (add_val ls (car param) (cdr param) #f '())))
      (else (find_val ls param))
      )
    )
  )
)